1. Tuberculosis
Is curable

2. Basics
 An chronic infectious disease
 Caused by Mycobacterium tuberculosis
 Roughly 1/3rd
of world’s pop.- infected
 India has 2 million new patients/year
 Problems-
 Drug resistance
 TB in AIDS

3. Transmission
 From people with active TB
 Inhalation of infected aerosol droplets
 Increased risk with prolonged, frequent & intense
contact
 Other risk factors for active disease-
 Malnutrition
 Diabetes mellitus
 HIV/AIDS
 Immunocompromised- steroids, transplant, malignancy
 Gastrectomy
 Silicosis

4. Pathogenesis
 90% infected are asymptomatic, with 10%
chance of active TB
 Primary infection- lungs ± LN- Ghon’s focus
 Spread by hematogenous route
 Secondary infection- in all organs, rare
in heart, muscle, pancreas, thyroid
 Characterised by caseating granulomas
 Healing by fibrosis

5. Presentation
 75% pulmonary

Fever, hemoptysis, productive cough x >3 weeks, wt. loss
 25% extrapulmonary
 Pleuritic
 CNS- meningitis, tuberculoma
 Lymph node- scrofula
 Urogenital
 Bone & joint- Pott’s disease
 Miliary (disseminated) TB- rare

6. Diagnosis
 Definitive- AFB detected (acid
fast staining or culture) in a
clinical sample
 Supported by-
 Suggestive history
 CxR- UZ lesion, cavitation, miliary infiltrates
 Raised ESR
 Montoux test- 0.1 ml of 5-TU PPD intradermally
 Interferon-gamma release assay (IGRA)
 ADA- pleural fluid, ascitic fluid, CSF

7. Classification- WHO
 Case definition-
 Suspect- based on symptoms/signs
 Case- diagnosed by a clinician for full course of ATT
 Definite- AFB +ve
 Site- pulmonary or extrapulmonary (name)
 Bacteriology results- smear +ve/-ve or not done
 History of previous treatment
 HIV status

8. Aims of treatment
 Cure & restore quality of life
 Prevent morbidity & mortality from
active disease
 Prevent relapse
 Reduce transmission
 Prevent development & transmission of
drug resistance

9. Treatment
 Multiple drugs, longer duration
 1st
line drugs
 INH- H- bactericidal against replicating bacteria
 Rifampicin- R- bactericidal with sterilizing effect
 Pyrazinamide- Z- effective intracellularly, in acidic environment & in
areas of acute inflammation
 Ethambutol- E- bactericidal at doses used
 Streptomycin- S- ensured bioavailability, good CSF penetration
 Standard regime
 2HRZE (intensive) + 4HR (consolidation)
 Dose

H-5, R-10, Z-25, E-15 mg/kg
 Administered daily

10. Treatment- contd.
 Side-effects- commoner in HIV +ve, elderly, underlying
liver disease
 H- hepatitis, sensory neuropathy (Pyridoxine)
 R- coloring of body fluids, flu-like syndrome, pruritis,
hepatitis, thrombocytopenia
 Z- hepatitis, polyarthralgia, hyperuricemia
 E- retrobulbar/peripheral neuritis
 Change, if required
 Longer duration- CNS TB, bone & joint TB
 Steroids- meningeal or pericardial TB
 S for E- CNS TB

11. Monitoring
 In smear +ve patients
 At the end of 2 months intensive phase, no change in drug used
 If +ve, at the end of 3 months
 If +ve, culture & sensitivity
 Prove smear negativity at the end of treatment in all
smear +ve patients at the beginning of treatment
 Monitoring of symptoms & weight
 No regular monitoring of SGPT or CxR

12. Treatment outcome
 Cure- smear/culture +ve-ve
 Treatment completed
 Treatment failure- smear/culture +ve at
5 months of treatment
 Default- Rx interruption for 2
consecutive months
 Death- for any reason during Rx

13. Previously treated
 All patients should have specimen
taken for culture & sensitivity (DST)
 DST at least for INH & Rifampicin
 Default- 2HRZES/1HRZE/5HRE
 Relapse- 2HRZES/1HRZE/5HRE
 Failure- empiric MDR regimen

14. Drug resistance
 MDR- resistance to INH & rifampicin
 DST- conventional (solid/liquid medium) or
rapid molecular line
probe assays
 DST recommended in-
 Previously treated for TB
 HIV +ve
 Active TB after exposure to one with MDR-TB
 Sputum +ve after 3 months of ATT
 All new patients if MDR >3%
 new patients- 3%, previously treated- 15%

15. Treatment of MDR-TB
 At least 4 drugs (1 from each group)
 Group 1- PZA, EMB, rifabutin
 Group 2- kana/amika/strepto-mycin
 Group 3- levo/moxi/o-floxacin
 Group 4- PAS, cycloserine, ethionamide
 Group 5- ?- unclear role
 Total of 18-24 months, with minimum of 6 months of
intensive phase (duration depends on smear/culture
negativity)
 XDR- resistance to H+R+Q+Aminoglycosides

16. TB and HIV
 All patients with TB to be tested for HIV
 Standard ATT for HIV +ve with TB, after
collecting sample for DST
 Add co-trimoxazole prophylaxis
 Start ART within 8 weeks of starting
ATT, irrespective of CD4 count
 Preferred ART- 2NRTI + Efavirenz

17. Special situations
 Pregnancy/Lactation- standard ATT, with
pyridoxine supplementation
 Liver disorder- If SGPT >3 times elevated
 9HRE or 2HRSE/6HR or 2HES/10HE or 18SEQ
 Increased incidence of hepatotoxicity, monitor
 Renal failure- 2HRZE/4HR,
but Z & E given thrice weekly

18. Prevention
 Vaccine- BCG
 Effective in preventing extra-pulmonary TB in children
 Part of UIP in India
 Screening- high-risk individuals
 Montoux tuberculin skin test
 Interferon-gamma release assay